Sporting Kansas City’s unique relationship with the Livestrong cancer charity founded by disgraced cyclist Lance Armstrong ended abruptly on Tuesday because of an apparent dispute concerning financial contributions promised by the MLS club.

Under the six-year agreement announced in the spring of 2011, Sporting donated the naming rights to its state-of-the-art, 18,400-seat facility as part of an effort to raise a reported $7.5 million for Livestrong.

It's just Sporting Park now; Livestrong is out after the charity and club decide to end their partnership. (AP Photo)

ESPN.com reported Tuesday that SKC was told that it had paid only one quarter of the $1 million it owed Livestrong for 2012. The club denied it was in arrears. The charity’s CFO, Greg Lee, said, “If a partner is struggling to meet the terms of our agreement, we do everything possible to reach a fair and reasonable compromise. If no compromise can be reached, as good stewards of our brand and mission, we have no choice but to bring that agreement to an end."

“There have been several instances over the last 22 months when our partnership with Livestrong has been called into question, both by media and the general public,” he said. “Throughout this entire period, we have staunchly defended the Livestrong mission and never wavered in our continuing support of the cause. Our plan was that through collaborative support from Livestrong, we would not just meet our stated donation goal, but exceed it by a wide margin.”

Heineman then claimed that in recent months “it became clear that Livestrong no longer shared the same spirit of partnership, despite our perseverance to the contrary,” and that it began “utilizing aggressive tactics designed to force us into an unsatisfactory arrangement.”

Both sides said the relationship had been terminated. ESPN suggested that Livestrong’s part in dissolving the partnership “would be the latest of several (moves designed) to separate itself from (Armstrong).” Row 1, Seat 7 in the stadium’s owners’ suite is fashioned out of bright yellow leather in honor of Armstrong’s seven Tour de France titles.

“We willingly admit we were not expecting the foundation to treat a partner in this manner,” Heineman said. “Even more surprising is that Livestrong would take this action in the midst of a significant transitional phase for their organization.”

Armstrong stepped down as chairman of the charity last October after the U.S. Anti-Doping Agency released a damaging report against him. He apologized to Livestrong staffers Monday prior to his interview with Oprah Winfrey. Armstrong later admitted to Winfrey that he used performance-enhancing drugs in his career.

SKC’s stadium now will be known as Sporting Park. Opened in June 2011, it already has become one of American soccer’s most popular venues. It hosted a World Cup qualifier, the U.S. Open Cup final and the men’s Olympic qualifying tournament last year and will be the site of the 2013 MLS All-Star Game.